This invention relates to a motion vector detecting apparatus suitable in carrying out correction of unintentional movement of the hands of, e.g., a video camera.
FIGS. 1A and 1B are views for explaining motion vector in a picture.
At present, in order to prevent distrubance (blurring) of an image, which takes place by unintentional movement (trembling) of the hands of a video camera, there is known a technique to detect movement of an image by unintentional movement of the hands to permit an image to be corrected by motion vectors obtained by detection of unintentional movement of the image.
Hitherto, in order to detect motion vector, as shown in FIG. 1A, a picture 1 taken is divided into a plurality of blocks to assume respective blocks as detection windows la to detect the direction of movement and a quantity of movement per each block. Then, a mean value of all the motion vectors which have been detected from the respective detection windows 1a of the picture 1 at a motion vector detecting circuit.
However, in FIG. 1B, in taking, by using a video camera, a picture of a moving object 1b moving from the right to the left of the picture 1, if this video camera fluctuates from the upward direction to the downward direction of the picture 1, different motion vectors All and C11 would take place within the picture 1. In this figure, a vector occurring by fluctuation of the video camera is a motion vector A11, a vector occurring by movement of the moving object 1b is a motion vector B11, and a resultant vector of the motion vectors A11 and B11 is a motion vector C11.
In FIG. 1A, motion vectors C11 are detected from detection windows 1a encompassed by dotted lines, and motion vectors All are detected from detection windows 1aexcept for the above. The moving object 1b corresponds to the detection windows 1a encompassed by dotted lines.
Meanwhile, the above-described motion vector detecting circuit for averaging motion vectors detected from all the detection windows 1a to detect it as a motion vector of the picture 1 detects a motion vector of the picture 1 as an average value of the motion vectors A11 and C11.
Accordingly, the conventional motion vector detecting circuit was unable to detect the motion vector A11 by itself. In this connection, the motion vectors A11 are necessary for preventing disturbance (blurring) of an image occurring by unintentional movement of the hands of a video camera.